Part 4

[8] The proposition here stated is applicable to any planet. It is probable that Mars, Venus and Mercury have passed through periods corresponding to our Ice Age; and that Jupiter, Saturn, Uranus and Neptune have not reached theirs. A study of Jupiter in this connection is particularly instructive. Phenomena are presented which are easily explained by the theory under discussion. See Zenographical Fragments, London, 1891. Also the author’s views in _Circulation of the Atmosphere of Planets_. Trans. Technical Society of the Pacific Coast, Vol. XI, No. 4, pp. 127-143.

[9] There were circumstances protecting certain areas, such as the “Unglaciated Area,” in the basin of the Yellowstone River, in North America. Here vast and continuous lava overflows in Wyoming, Idaho, Oregon and Washington, liberated earth heat; which heat, borne easterly by the general circulation of the atmosphere, caused the precipitation upon the “Unglaciated Area” to be warm rains instead of snow. To this region the animals of the tertiary period retreated as glacial conditions surrounded them. Here they were protected, and perpetuated their species, and in these regions vast quantities of their remains are found. _Mining and Scientific Press_, Feb. 14, 1892.

The easterly projection of the unglaciated area is opposite the corresponding projection in the lava overflow. How this simple explanation has escaped the researches of geologists is not known.

[10] Maury, _Physical Geography of the Sea_, 6th Edition, p. 212, _et seq._ Croll, _Climate and Time_, p. 60, _et seq._ Also, Climate and Cosmology, p. 51.

[11] Except hydrogen.

[12] Moreover, in cooling the subjection of one pole to glacial and the other to temperate or sub-tropical conditions, as argued by Dr. Croll, would have subjected our planet to very peculiar “cooling strains,” as they are termed by foundrymen. Whereas the slow and uniform cooling, as herein described, is productive of maximum thickness, strength and uniformity of crust; and, as will be explained later, this crust was finally shrunk in upon the interior mass by being subjected to the maximum degree of cold to which it can be exposed during the existence of the sun as a source of heat.

[13] The prime objection which is urged against all previous theories is their inadequacy. We here have a perfectly adequate cause--resident earth heat to supply evaporation and shut out solar energy, which energy can only act the part of a conservator of the glacial conditions until the exhaustion of earth heat, when its power can be spent in melting glacial ice, and in gradually establishing the present conditions.

[14] It will again be noted that the isotherms inside of 32° - y° Far. were maintained by earth heat, and therefore independent of equatorial or polar exposure to solar heat. Consequently their intersections were upon different lines from those isotherms exterior to 32° - y° Far., which latter were mainly dependent upon solar heat. It will also be observed that solar heat, when it reaches the lower, denser regions of the atmosphere, is trapped and therefore capable of establishing and maintaining higher temperatures than in the upper atmosphere.

[15] The truth of this fact is easily established by either observation or experiment. At the close of a hot day should a slight cloudiness supervene, the loss of heat by radiation from the surface is checked; the air at the surface, and the surface, remain at the same temperature, and nature’s delicate differential thermometer--the deposition or non-deposition of dew--records the non-transcalency of clouds, in terms worthy of consideration.

Again, let two delicate thermometers be exposed, one to the air temperature and the other in addition to direct solar rays; the latter will mark the increased temperature due to such exposure. Upon the intervention of a cloud, or even a jet of steam, both instruments will mark the same temperature.

See Physical Geography of the Sea. Maury, 6th ed., p. 212, _et seq._ Climate and Time, Croll, p. 60, _et seq._ Climate and Cosmology, Croll, p. 51.

[16] Astronomers agree that there must exist upon Jupiter a high degree of heat, and yet no refinement of thermometric determinations can detect any more heat from the Jovian surface than should be reflected from the sun.--See _Young’s General Astronomy_, page 353; also _History of Astronomy During the Nineteenth Century_. Clerke, pp. 335-338.

[17] The author is aware that this statement is at variance with the opinion of many Geologists of high repute, as may be seen from the following quotations: “It is evident that the idea of connecting the phenomena of the internal heat of the globe with terrestrial climates, whether of the present or of past geological ages, must be entirely abandoned, as it has been, by most writers on this subject. The hypothesis cannot be allowed to stand as even one of the possible theories of climatic change.”--_The Climatic Changes of later Geological Times._ Whitney, p. 261.

“The first theory brought forward to account for glaciation was that the earth, having been originally in a fiery state, had in cooling passed from a condition of universal warmth to a more and more frigid state, until the present conditions were attained. This is the least tenable of all theories, for it neglected the now evident fact that there had been changes from cold to warmth and back again to cold. However, as it was invented before the existence of glacial periods was suspected, it long commanded a general assent, and was the opinion that held the ground until near the middle of this century.”--_Glaciers._ Shaler & Davis, p. 70.

The physicists who have held that earth heat was a cause of the Ice Age are Prof. E. Frankland, F. R. S., Prof. A. Woeikof and Startorius von Walterhausen. Not one of the three, however, seems to have had a clear conception of all the facts and conditions although their views were in the main sound.

The author hopes to extend the views held by these writers and to show that the whole range of climates as recorded by fossil and existing life is capable of correct interpretation, in accordance with known laws, and without the intervention of suppositions and assumptions. And moreover, to base his deductions upon a general plan applicable to any planet and capable of explaining conditions prevalent upon other planets, notably upon Jupiter and Mars.

[18] To those interested in a verification of this very wide distribution of glaciation, the following short list of authorities is recommended:

_Asia._--The Great Ice Age (Giekie); Note on the Glaciation of parts of the Valleys of Jhelan and Scind Rivers, in the Himalaya Mountains of Kashmere, Lat. 34° N. (Capt. A. W. Sleff), F. G. S.; Jour. Geol. Soc., London, vol. xlvi, p. 66; Mem. Geol. Survey of India, vol. xxii, also vol. xiv; Record Geol. Survey of India, Nov., 1880; Jour. Asiatic Society, Bengal, xxxvi, p. 113; Brit. Association Report, 1880; Text Book of Geology, A. Giekie, LL. D., etc., p. 911.

_Europe._--The European Glacial Literature is too extensive to mention.

_America._--The Ice Age in North America (Wright); U. S. Geological Reports; State Geological Reports of Ohio, Kentucky, Pennsylvania, New York, Minnesota, Nebraska, Colorado, Illinois, etc.; Virginia, Am. Jour. Sci., vol. vi, p. 371; California, Am. Jour. Sci., vol. iii, p. 325, vol. x, p. 26.

_South America._--Geological Sketches, Agassiz, p. 154, _et seq._; Geol. and Physical Geog. of Brazil (Prof. Ch. Fred. Hartt), pp. 22, 28-9, 469-70, 490, 558.

_Africa._--Geol. of South Africa (Stow); Quart. Journ. Geol. Soc., London, vols. xvii and xviii.

_Australia and New Zealand._--Climate and Time (Croll), p. 295; Am. Jour. Sci., vol. 32, third series, p. 224; Proc. Linnæan Soc., N. S. W., May, 1886; Prestwich’s Geol., vol. ii, p. 467; Rep. Brit. Assn., 1881, p. 742.

“The shrunken or vanished ice of mountain ranges is indeed equally characteristic of the Himalaya, the Lebanon, the Alps, the Scandinavian chain, the great chains of North and South America, and of other minor ranges and clusters of mountains.”--Ramsay, Quart. Jour. Geol. Soc., 1862, p. 204.

[19] Many geologists are misled by the greater modification of tropical drift by sub-aerial agencies. Having been longer exposed to such agencies, greater modifications are to be expected. The apparent improbability of tropical glaciation seems to deter many scientists from believing that such glaciation could ever have occurred, yet the same scientists will accept the fact that fossil life establishes the existence of tropical or even torrid conditions within the polar circles during past ages.

[20] See Geological Sketches, Agassiz, p. 154, _et seq._ Also Physical Geography and Geology of Brazil, Prof. Ch. Fred. Hartt, pp. 22, 28, 29, 217, 469, 470.

[21] See the author’s views in _Physical and Geological Traces of Permanent Cyclone Belts_. Trans. Technical Society of the Pacific Coast, Vol. VIII, No. 1, June, 1891.

[22] Phil. Mag. (4), Vol. XXV, pp. 1-14. Trans. Royal Soc. Edin., Vol. XXIII. Influence of the Earth’s Secular Heat upon Climates. Hopkins, Jour. Geol. Soc., Vol. VIII.

[23] Climate and Time, Climate and Cosmology.

[24] The Cause of an Ice Age, chapters 5 and 6.

[25] Nature, May 1891; S. E. Bishop.

[26] Circulation of the Atmosphere of Planets.--Trans. Technical Soc. of the Pac. Coast, Vol. IX, No. 5; pp. 136-143.

[27] For a further discussion of the conditions prevalent upon Jupiter see _Circulation of the Atmosphere of Planets_, previously quoted.

[28] Except hot or warm lava covered areas, and the protected or “unglaciated areas” to the eastward of such lava overflows. (See page 44 and note [9] page 14.)

[29] The Columbian Lava Plains of North America aggregate some 150,000 square miles; the Deccan Lava Plains of India cover an almost unbroken plain 200,000 square miles in area. No Geologists ascribe these lava overflows to an earlier date than the Tertiary; the author could find no reason to assign the Columbian Lava Plain to so early a period, and strong reasons to assign the continuance of the flow to the later Quaternary; of the Deccan Plain he is unable to speak. (See Trans. Geological Society of Australasia, vol. i, part vi, p. 162, note. Also Mining and Scientific Press, Feb. 6th, 1892.)

[30] _Climatic changes indicated by Glaciers._

Prof. I. C. Russell, Am. Geologist, May, 1892, vol. ix, No. 5. In addition to the very extensive list of authorities there quoted by Prof. Russell, see also Report of The British Ass’n. 1881, p. 742.

Life of Agassiz, Vol. II, pp. 717 to 729 and pp. 743 to 747.

[31] At the culmination of the Ice Age evaporation reached its minimum, and hence precipitation was also at a minimum. Since that Age evaporation has slowly increased; the amount of moisture in the atmosphere being dependant upon its temperature, this amount has also increased. The aggregate amount of evaporation and the aggregate amount of precipitation is slowly increasing, and has the moderate limit fixed by natural laws for increase of mean temperature. Mars appears to have progressed further in this mean condition than the earth. The smaller mass partly accounts for this.

[32] Archives des Sciences, vol. v, p. 293. Proc. Royal Soc., vol. xiii, p. 160.

[33] Archives des Sciences, Berne, vol. lvii, p. 293, _et seq._

[34] Dr. Cleveland Abbe, U. S. Meteorological Bureau. Am. Jour. of Science, May, 1892, vol. xliii, p. 364.

[35] The albedo of Jupiter is 0.62; that of Mars, 0.26, of the moon 0.174. It will be observed that the planets distinctly shrouded in clouds have high reflective powers; those planets and satellites not shrouded have very low powers. Venus, in this respect, seems to have a partially obscured atmosphere, her albedo being 0.50.

[36] General Astronomy.--Young; p. 337.

[37] Venus presents a condition which suggests that she may be partly shrouded in clouds, shutting out solar heat, just as the thermal equator of the earth is thus partly protected by the equatorial cloud ring.

TRANSCRIBER’S NOTE

Page 6: “unequal subaerial denudation” changed to “unequal sub-aerial denudation”

Page 16: “two spheroidal iostherms” changed to “two spheroidal isotherms”

Page 25: “whole system of preglacial” changed to “whole system of pre-glacial”

Page 30: “at variance with those ante-dating” changed to “at variance with those antedating”

Page 31: “less in the Antartic” changed to “less in the Antarctic”

Page 33: “lowered one hundreed” changed to “lowered one hundred”

Page 35: “way into a subtropical growth” changed to “way into a sub-tropical growth”

Page 35: “are really coroborative” changed to “are really corroborative”

Page 46: “maintaining the cloud envelop” changed to “maintaining the cloud envelope”

Page 48: “light received by the earth” changed to “light received by the earth.”

Footnote 4: “la Mer. Déluges Périodique” changed to “la Mer. Déluges Périodiques”